Re: [PATCH] perf: use default compiler mode by default

Ingo Molnar
2009-11-22T12:59:21Z

* Michael S. Tsirkin <mst@redhat.com> wrote:

> gcc with no flags typically is a sane default for systems to use, and
> looking at the running kernel is probably broken for cross-builds
> anyway, so let's not do this. Add EXTRA_CFLAGS so that users can
> override default gcc mode if they want to.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> tools/perf/Makefile | 20 +++-----------------
> 1 files changed, 3 insertions(+), 17 deletions(-)
>
> diff --git a/tools/perf/Makefile b/tools/perf/Makefile
> index d0bdaf2..ab35b0f 100644
> --- a/tools/perf/Makefile
> +++ b/tools/perf/Makefile
> @@ -148,6 +148,8 @@ all::
> # broken, or spawning external process is slower than built-in grep perf has).
> #
> # Define LDFLAGS=-static to build a static binary.
> +#
> +# Define EXTRA_CFLAGS=-m64 or EXTRA_CFLAGS=-m32 as appropriate for cross-builds.
>
> PERF-VERSION-FILE: .FORCE-PERF-VERSION-FILE
> @$(SHELL_PATH) util/PERF-VERSION-GEN
> @@ -160,22 +162,6 @@ uname_R := $(shell sh -c 'uname -r 2>/dev/null || echo not')
> uname_P := $(shell sh -c 'uname -p 2>/dev/null || echo not')
> uname_V := $(shell sh -c 'uname -v 2>/dev/null || echo not')
>
> -#
> -# Add -m32 for cross-builds:
> -#
> -ifdef NO_64BIT
> - MBITS := -m32
> -else
> - #
> - # If we're on a 64-bit kernel (except ia64), use -m64:
> - #
> - ifneq ($(uname_M),ia64)
> - ifneq ($(patsubst %64,%,$(uname_M)),$(uname_M))
> - MBITS := -m64
> - endif
> - endif
> -endif

iirc PowerPC had some trouble in this area. Paulus?

Ingo